That’s a lot of the cooking elements that people try to run off inverters. And on days I do get it, I can put out my 5th portable panel and dump 20 AMPS an hour into the lithium’s when I can. We have a chart in our vent fan article ( which shows the amperage draw for the Maxxfan and Fantastic Fan at each setting. Thank you for any help. Thinking if I have just 1 and it stops working for some reason, then I have no reserve. Battery Type We spent over two years living in a DIY camper van and visiting 48 US states. So in this case were using 1127 watt hours per day. And then we have recommended components for those specific sizes. If I am consuming a certain amount of power throughout the day, then the solar panels alone must be able to source that power. If you have sleep apnea and you have a breather that you need on you, you can boost your battery size to make sure that you have juice to run a few days without recharging. Select whether your device is DC powered or will be using an AC inverter. AC components are running off of your inverter. ABOUT US Some general rules to follow are: We based our calculations on a 10% efficiency loss that occurs when using an AC inverter. A lot of this stuff is variable and that’s why the solar diagrams you see online get kind of wonky and complicated because they’re for very specific set ups. In cold weather, the compressor in a fridge may only be. So 4 sun hours, gives us 220 watts of solar. For instance, if you need 150W of power, but your system is only 75% efficient, then you would need 200W of panels to get 150W into the batteries. so is there a book and or a diagram that helps explain this from each unit. Is there any reason I cannot simply connect the solar to batteries outside the camper, and connect the Shoreline to the inverter? In series wouldn’t the CC stepping down use some of the potential power? I wish I had come across this 2 years ago when I was building out my van and trying to figure out all this stuff. If you occasionally are using more power – such as a hair drier for a few minutes once a week – then you won’t be doing too much damage to your batteries. When using a crystalline solar panel, remember that even the tiniest shadow can affect the amount of power generated. It’s mostly plug and play and it’s pretty fun doing it on your own not only because you save some money and you can have a system sized exactly to what you need it, but it also helps you diagnose issues later down the road if you know what’s going on. An inverter is less efficient. Living in a van requires cutting down on unnecessary electronics as much as possible.  Rigid Monocrystalline  75Ah (x1) Battery (AGM option) Read our wiring guide for more details on how to size your specific system.  Adjustable tilt mount (optional) You don’t want to grab a massive inverter just in case you want to run a power tool or something off of it. Rates are based on a 12V system with 5 hour charging times. I can’t connect the inverter to the van’s battery for obvious reasons. What you’re going to want to do is everything that uses electricity, you’re going to write down.  Battery monitor (optional – basic) The best option is a battery to battery charger, many of which double as a solar charge controller. Now because of this, my laptop is only plugged in and charging about 2 hours per day. So this is where that [inverter] number is coming from. Because each day is like its own reset in terms of the electricity that you’re going to use. Thanks so much!!! This is for all you do-it-yourself (DIY) solar system sizing folks out there. All I’ve been able to find are rings, spades or slabs. If you have, let’s say you’re going to be in the desert southwest most of the time and you know you’re going to have tilt mount panels maybe you’ll see 6 hours of sun. Your wire size is going to vary greatly depending on how far you are running them. So sometimes smaller systems, say in this case, let’s say you find a couple of 150 watt hour panels 160 watt panels – if you go 300 watts of solar and a PWM controller, you’re going to be paying less for more power than if you were to go with an MPPT controller. has a number of ways to help you find the right system for your RV, boat or work truck. In hotter weather that compressor is going to be on a lot more because that internal temperature is going to raise up a lot.  Flexible polycrystalline, Solar Panel Kits Due to the controller needing to adjust voltage to charge properly, some power is lost to the system. I use a good bit of power because I work from my van. So, with that said, an MPPT charge controller has the ability to “convert” the extra voltage above that charge level to amperage, thus using as much energy as possible for charging the batteries. So the reason you don’t want to go bigger on your inverter for this is because a bigger power draw is hard on your batteries, it’s going to make them not last as long. Solar Sizing for Your RV. There are small caveats that an expert may adjust for specific combinations of components to increase longevity or efficiency, but the complexity is overwhelming for a beginner so they are not covered. You show the loads directly tied to the battery. It is difficult to predict how much wiring each different van build will have and the lengths needed, and we don’t want to have you ordering things that you don’t need. We have a cool solar panel calculator on our site and i’m going to walk you through how to use it because there are a lot of steps involved and sometimes just seeing someone go through it helps quite a bit. These are the component sizes I’m going to go with.  Battery monitor (optional) Now if you’re not familiar with working with electricity at all, you should probably have a professional or a mentor of some kind helping you through this. Say this number comes out to 25 amps, but you know your MPPT specs say that it can go to 240 watts and you only have 220 watts of solar, that charge controller can be a 20 amp charge controller. Your email address will not be published. Regards, Get. So they can’t supply all of that charge throughout the day like your batteries are going to be able to discharge. Solar System If it’s not even charging the battery, if it’s just plugged in and idol it’ll be down in the 50 watt range. If DIY solar power is intimidating to you, we recommend looking at solar powered generators which are plug and play devices that require little to no wiring. So this component is our general go-to if we were to build a camper van with our own money this is how we would use it. Hey Ross, good catch! We fund our effort and research through affiliate links and advertising, so just by being here and using the site you’re thanking us. We like to use watt hours because it’s a more accurate estimate of actual power usage, because amps are determined by your voltage.  20A PWM (budget option) As an Amazon associate we earn from qualifying purchases. In you situation, you would indeed be dropping significant voltage because of your choice of PWM controller. Then build your system to the largest number. Used to reduce electricity bill. As per the Solar panels, we need to pay attention to the working voltage and short-circuit voltage. I’m not sure exactly where in the formula the 1.2 and 1.3 come in the way we set up the calculator (it was awhile ago), but you’ll notice that with an MPPT system, you need less wattage in panels than a PWM one because MPPT controllers are more efficient. Here are some tips to cut back on electronic use.  Solar panel roof mounting z-rack (optional)  Battery isolator The calculator takes into account the power consumption you use in your caravan/RV and your travel destinations. Copyright © | Disclosure: We are a participant in the Amazon Services LLC Associates Program. So once you have that all figured out, how do you put it all together?  50Ah (x1) Battery (Lithium option), Additional Parts Watch the video below if you’re not sure how to fill out the calculator. Your battery can be either AGM and FLA (those are both lead acid battery types). Thank you so much! 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